diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 63b5a8b6dfb..609868f3db4 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -448,8 +448,9 @@ struct nand_buffers {
  *			will be copied to the appropriate nand_bbt_descr's.
  * @badblockpos:	[INTERN] position of the bad block marker in the oob
  *			area.
- * @badblockbits:	[INTERN] number of bits to left-shift the bad block
- *			number
+ * @badblockbits:	[INTERN] minimum number of set bits in a good block's
+ *			bad block marker position; i.e., BBM == 11110111b is
+ *			not bad when badblockbits == 7
  * @cellinfo:		[INTERN] MLC/multichip data from chip ident
  * @numchips:		[INTERN] number of physical chips
  * @chipsize:		[INTERN] the size of one chip for multichip arrays